(Noun) A private technology company that was formerly valued at $1bn or more (slang, vulg)
Silicon Valley is nothing if not inventive, and that applies to language as much as product development. Three years ago, Aileen Lee, founder of Cowboy Ventures, coined “unicorn” to capture the phenomenon of private technology companies achieving valuations of $1bn and more. She likened these desirable ventures to the mythical horned creature often represented in the shape of a horse.
More recently, in response to the declines in value of some unicorns, Ms Lee has concocted a less mythological variant: the “unicorpse”. It is one of a number of unicorn-related neologisms, including “My Little Pony” (a start-up worth $10m or more), the “Centaur” ($100m start-up) and the impressive “quinquagintacorn” (you work it out*).
--Financial TImes (article available for subscribers only)
A "unicorpse" is a dead unicorn -- a startup that gains a valuation of more than $1 billion, then declines and fails before going public. This hasn't happened yet, but some say that Evernote might become the first "unicorpse."